Variants of lipopeptides produced by Bacillus licheniformis HSN221 in different medium components evaluated by a rapid method ESI-MS

A lipopeptide producing strain was isolated from an oil field and identified as Bacillus licheniformis HSN221. Nine different substrates were used to cultivate the strain under the same incubation conditions. Using a rapid method, Electrospray Ionization Mass Spectrometry (ESI-MS) combined with Thin Layer Chromatography (TLC), nine different lipopeptide homologues were found and identified. The strain produced four [Leu]surfactin homologues, surfactin C13, surfactin C14, surfactin C15 and surfactin C16, when cultivated in the medium with glucose, yeast extract and ammonium chloride, but it produced five lichenysin homologues, lichenysin C12, lichenysin C13, lichenysin C14, lichenysin C15 and lichenysin C16, when cultivated in the remaining eight media. Additionally, it showed that the type and relative content of each homologue were consistent with in each medium which is helpful for optimizing the medium components to cultivate the similar species.